Baseball and softball bat manufacturers are continually attempting to develop low cost, lightweight ball bats that exhibit excellent durability and performance characteristics. Ball bats typically include a handle, a barrel, and a tapered section joining the handle to the barrel. A knob is typically attached to the free end of the handle, and a cap or other barrel closure is typically attached to the free end of the barrel. The outer shell of these bats is generally formed from aluminum or another suitable metal, and/or one or more composite materials.
Aluminum, or other metal, knobs are typically attached to metal ball bats via welding. Pins, screws, bolts, or other suitable attachment elements are alternatively used to attach the knobs to the bats. Aluminum knobs are desirable because they are durable, and are also relatively lightweight and inexpensive. Durability of a bat knob is important, as knobs are often subjected to stresses or forces when they are struck against a surface, such as when a batter slams the knob of a bat into the ground after striking out. Thus, aluminum knobs are generally preferred over less durable knobs in bat manufacturing.
Aluminum knobs cannot, however, be welded or otherwise readily attached to a composite, or other non-metal, bat handle. A common method for attaching a knob to a composite bat handle is to cast a polymer knob at the free end of the predominantly cylindrical bat handle. Structural integrity of the knob attachment is typically enhanced using one or more containment devices, such as pins and/or bolts.
The polymer knob is typically cast around the pins or bolts in order to improve the knob's structural performance. Unfortunately, the use of pins and bolts has a significant impact on the cost of manufacturing and the overall weight of the bat, and attaching a knob in this manner is a relatively lengthy process. Furthermore, polymer knobs are not nearly as durable as aluminum, or other metal, knobs. Thus, there is a need for a lightweight, low cost, durable knob that can be attached to a composite, or other non-metal, ball bat.
Attaching durable barrel caps to composite, or other non-metal, bats presents similar challenges. And barrel caps are more likely to be slammed into surfaces and struck by pitched balls, due to their location on the bat, than are bat knobs. Thus, there is also a need for a lightweight, low cost, durable barrel cap that can be attached to a composite, or other non-metal, ball bat.